Add NMS definition for 1.16.4

src/main/java/com/gmail/nossr50/util/compat/CompatibilityManager.java

@@ -124,6 +124,8 @@ public class CompatibilityManager {
                         return NMSVersion.NMS_1_16_2;
                     } else if(minecraftGameVersion.getPatchVersion().asInt() == 3) {
                         return NMSVersion.NMS_1_16_3;
+                    } else if(minecraftGameVersion.getPatchVersion().asInt() >= 4) {
+                        return NMSVersion.NMS_1_16_4;
                     }
             }
         }

src/main/java/com/gmail/nossr50/util/nms/NMSVersion.java

@@ -20,6 +20,7 @@ public enum NMSVersion {
     NMS_1_16_1("1.16.1"),
     NMS_1_16_2("1.16.2"),
     NMS_1_16_3("1.16.3"),
+    NMS_1_16_4("1.16.4"),
 
     //Version not known to this build of mcMMO
     UNSUPPORTED("unsupported");